Gaseous fuel burner



y 13, 1941- D. A. CAMPBELL 2,

GASEOUS FUEL BURNER Filed Dec. a, 19:58

tgpgw Patented May 13, 1941 UETE STATES rrics GASEOUS FUEL BURNER Donald A. Campbell, Rockford, Ill., assignor to Garnet .W. McKee, Rockford, 111.

4 Claims.

The present invention relates generally to gaseous fuel burners for furnaces and other heating apparatus. More particularly the invention relates to that type of burner which is designed to burn a combustible mixture of air and gas and consists of a tube-like member which is adapted to have the mixture supplied to one end thereof under pressure, embodies at its other end means for connection to a combustion block in one wall of the furnace with which the burner is used, and has a longitudinal passage therethrough with a short inwardly tapered mouth, a comparatively long throat and an outwardly flared outlet.

One object of the invention is to provide a gaseous fuel burner of this type which embodies a novel and comparatively simple device for igniting the fuel mixture passing through the passage in the tube-like member in connection with starting of the burner.

Another object of the invention is to provide a burner of the last mentioned character in which the igniting device for the fuel mixture is in the form of a Bunsen burner which is exteriorly disposed with respect to the tube-like member, is adapted to be lit by a torch or a match and is arranged and designed so that when it is ignited or lit in connection with starting of the gaseous fuel burner, it operates to direct a jet of flame through a duct in the tubelike member into the longitudinally extending passage.

A further object of the invention is to provide a gaseous fuel burner of the type and character under consideration which includes simple means for closing the duct in'the tube-like member after the igniting device has been extinguished at the conclusion of the burner starting operation.

A still further object of the invention is to provide a gaseous fuel burner in which the igniting device is an improvement upon and has certain advantages over that which is shown in and forms the subject matter of United States Letters Patent No. 2,105,344, granted to me January 11, 1938.

Other objects of the invention and the various characteristics and features of the present gaseous fuel burner will be apparent from the following detailed description.

The invention consists in the several novel features which are hereinafter set forth and are more particularly defined by claims at the conclusion hereof.

In the drawing which accompanies and forms a part of this specification or disclosures and in which like numerals of reference denote corresponding parts throughout the several views:

Figure l is a vertical longitudinal section of a gaseous fuel burner embodying the invention; and

Figure 2 is a vertical transverse section taken on the line 22 of Figure 1 and illustrating in detail the construction and design of the means for closing the duct in the tube-like member after starting of the burner and extinguishment of the igniting device.

The burner which is shown in the drawing constitutes the preferred embodiment of the invention and is characterized by the fact that it includes a simple and novel igniting device. It is designed to burn a combustible mixture of air and a gas such as butane or natural gas, comprises a tube-like member 3, and is adapted primarily for use in connection with a furnace F having a combustion block f. The furnace embodies a side wall i which has, as shown in Figure 1, a hole f for the combustion block I. The

block projects outwardly a small distance be-' yond the side wall and embodies at the outer end thereof an entrance f. The latter is cylindrical and communicates with the interior or fire box of the furnace F by means of an inwardly flared fire tunnel f. A facing f of heat insulating material surrounds the projecting end of the combustion block and is held in place against the outer face of the side wall of the furnace by means of a metal facing i which abuts against the outer end of the combustion block and embodies a circular opening I in registry or alignment with the cylindrical entrance f of the fire block.

The tube-like member 3 of the burner is axially aligned with the combustion block f, as shown in Figure l of thedrawing. It is formed of steel or any other suitable material and is adapted to receive the fuel mixture under pressure by way of a pipe 4. The discharge end of the pipe *3 abuts against one end of a nipple 5 and is secured in place by means of a coupling ring 6. The other end of the nipple fits around the inlet end of the tube-like member 3 and is connected to the latter by way of a screw thread 1. The inner or discharge end of the member 3 is in the form. of a reduced or stem-like extension 8 which extends through the hole f in the plate f and fits within the cylindrical entrance f of the combustion block 1. A ring type plate nected by a screw thread i!) to the stem-like extension 8 at the inner end of the tube-like mem her 3 and is clamped against the hole defining portion of the plate f by bolts II. The inner periphery of the tube-like member 3 defines a longitudinally extending fuel passage I2 through which the fuel mixture passes from the discharge end of the pipe 4 to the entrance f of the combustion block 1. The passage I2 embodies a short mouth I3, a narrow throat i4, and an outwardly flared outlet H5. The mouth is located at the inlet end of the member 3 and is inwardly tapered. The throat I4 extends from the mouth I3 to the stem-like extension 8 and there joins and communicates with the outlet I5. It is circular in cross-section and is of uniform diameter from one end thereof to the other. The outlet I5 is located in the stem-like extension 8 and discharges into the cylindrical entrance f of the combustion block 1. The fuel mixture in travelling through the passage I2 first enters the mouth I3, then flows through the throat I4 and finally passes through the outwardly flared outlet l5 into the combustion block. Due to the inward taper of the mouth iii, the velocity of the fuel mixture is materially increased as the mixture passes through the throat. This increased velocity of the mixture is maintained during flow of the mixture through the throat due to the fact that the throat is narrower than the mouth and is of uniform diameter from one end thereof to the other. When the fuel mixture passes into the outlet I5 of the throat l i, the velocity of the mixture decreases due to the outward flare of the outlet. Upon entry of the fuel mixture into the tunnel f in the combustion block, combustion takes place. During normal operation of the burner no combustion of the gas takes place in the throat I4. This is due to the fact that the velocity at which the mixture passes through the throat is above, that is, in excess of the rate of the flame propagation of the gas.

The igniting device is disposed exteriorly of the burner and is of the Bunsen burner type or variety. It is supplied wtih gas by way of a pipe I6 and comprises a compression fitting IT, a tube I 8, and a composite nozzle E9. The pipe I 3 is connected to any suitable source or supply of gas under pressure and includes a cock 20 and an adjustment valve 2|. The cock 2@ comprises a casing and a handle equipped plug 22. The plug is rotatably mounted in the casing and is adapted when shifted into one position to permit gas to flow through the cock casing 26 to the igniting device and when turned or rotated 90 to cut off the flow of gas through the cock casing. The adjusting valve 2i is interposed in the gas supply pipe between the cock 26 and the igniting device. It comprises a casing 23 and a handle equipped plug The plug is rotatably mounted in the casing and is adapted to be set or adjusted after installation of the burner so that upon opening of the cook only the proper amount of gas is delivered to the igniting device. The compression fitting I! of the igniting device is elongated and is connected at one end thereof to the discharge end of the pipe i6 by a coupling ring 25. The other end of the fitting embodies an orifice plug 23 and fits within and is connected by a screw thread 2i to one end of the tube I ii. The plug 26 is secured in place by a screw thread 23 and is designed to jet longitudinally through the tube 23 the gas which is delivered into the compression fitting I? when the cook 20 is in its open position. The composite nozzle I9 is axially aligned with the jet opening in the orifice plug 26 and consists of a sleevelike outer member I900 and an inner orifice member I531). The outer member is connected to the tube I8 by a screw thread 29 and has the inner orifice member secured thereto by a screw thread connection. The tube I8 is provided with a plurality of holes 30. These holes are positioned near the orifice plug 23 and permit air to enter the tube I8 for mixture with the gas emanating from the plug 26. The gas which is jetted through the tube I8 by the plug 26 and the air which it entrains constitutes a combustible mixture which is directed towards and flows through the nozzle I9. The compression fitting H, the tube l8, and the nozzle are located over the central portion of the tube-like member 3. They are inclined downwardly in the direction of the extension 8 and are supported by a bracket 3I. The latter is secured by bolts 32 to the top central portion of the tube-like member 3 and embodies at its inner end an upwardly inclined lug 33. The lower end of the outer member I9a, of the nozzle I9 extends through a hole in this lug and is connected to the latter by a screw thread 33a. The nozzle is disposed adjacent the juncture of the throat Hi and the outlet I5 of the longitudinal passage I2 in the tube-like member 3 and is axially aligned with a diagonal or inclined duct 3 in the extension 8. This duct leads to the inner end of the outlet I5 and has an enlarged chamber forming upper end. The gas and air mixture emanating from the nozzle while the cock 20 is in its open position is adapted to be i nited by placing a torch or match near the lower end of the nozzle. The flame issuing from the nozzle flows downwardly through the duct 35 and serves to ignite the fuel mixture flowing through the passage E2 in the tube-like member 3 into the fire tunnel 1' When starting the burner, air under pressure is first delivered to the tube 3. Thereafter the igniting device is ignited in order to produce a jet-like flame at the lower end of the nozzle I9. Such flame due to the suction created within the duct 34 by the air under pressure in transit through the passageway I2 is drawn downward through the duct into the outlet I5 of the passageway. As soon as the igniting device is ignited a mixture of gas and air under pressure is introduced into the passage I2 and this is ignited as it flows from the flared outlet I5 by the flame emanating from the lower end of the duct 34. By having the lower or inner end of the duct 34 intersect the fuel passage I2 at the inner end of the outwardly flared outlet i5, i. e., at a point slightly outwards of the juncture point of the throat and the outlet, the igniting device operates in a highly emcient and positive manner at all times even though there should be slight variations in the velocity or rate of flow of the gas and air mixture through the passage.

In order to close the duct 3t against the flow of air therethrough during operation of the burner, a collar 35 is provided. This collar surrounds the tube-like member 3 at the point where the upper enlarged end of the duct 34 intersects the outer periphery of the member 3 and embodies an opening This opening is adapted when the collar is positioned, as shown in Fig ure 1, to register with the upper enlarged end of the duct 34 and hence permits flame emanating from the nozzle to enter the duct 35. When the collar 35 is rotated so as to bring the opening 33 out of registry with the upper enlarged end of the duct 34, the duct is closed against the passage of air therethrough. An arm. 31 is connected to and extends radially from the collar 35 and forms a handle whereby the collar may be turned to bring the opening 36 into and out of registry with the upper enlarged end of the duct 34.

When it is desired to start the burner the collar 35 is rotated in order to bring the opening 35 into registry with the upper enlarged. end of the duct 34. While air under pressure is flowing through the passage I2 in the tube-like member 3 of the burner, the cock 20 is opened by proper manipulation of the handle equipped plug 22. As soon as gas and air start to emante from the nozzle N such mixture is ignited by applying a torch or match, as hereinbefore described. As soon as the mixture ignites and the flame is drawn downwardly through the duct 34 into the outlet l5 of the passage l2, the supply of air under pressure to the tube-like member 3 is cut off and the fuel mixture under pressure is then supplied into the passage l2. As soon as the mixture encounters the flame emanating from the lower end of the duct 34, it ignites and a main flame is produced in the fire tunnel f of the combustion block J. As soon as the fuel mixture is properly ignited the cook 20 is closed and the collar 35 is rotated by manipulation of the handle 31 to bring the opening 36 out of registry with the upper enlarged end of the duct 34.

The herein described burner with its igniting device is practical and efficient and may be produced at a low cost in view of the simplicity of the igniting device. Due to the fact that the igniting device is located exteriorly of the tubeand directing such flame toward the duct for passage to the passage in the member, and means for closing the duct against the flow of air therethrough after starting of the burner member.

2. The combination with a tube-like burner member having one end thereof adapted for connection to a combustion block in a furnace and its other end' adapted to receive gaseous fuel under pressure, and embodying a longitudinal fuel passage therethrough and a duct leading from the atmosphere surrounding the member to the passage, of an igniting device for the burner member comprising a Bunsen type burner adapted to produce a flame and positioned exteriorly of the member and also to direct the flame into the duct for passage to the passage in the member, and means for closing the duct against the flow of air therethrough after starting of the burner member.

3. The combination with a tube-like burner member having one end thereof adapted for connection to a combustion block in a furnace and its other end adapted to receive gaseous fuel under pressure, and embodying a longitudinal fuel passage therethrough and a duct leading from the atmosphere surrounding the membar to the passage, of an igniting device for like member 3 it is not subject to the heat of r the furnace F. In addition, the various parts thereof are readily accessible for inspection or replacement purposes.

The invention is not to be understood as restricted to the details set forth, since these may be modified within the scope of the appended claims, without departing from the spirit and scope of the invention.

Having thus described the invention, what I claim as new and desire to secure by Letters Patent is:

1. The combination with a tube-like burner member having one end thereof adapted for connection to a combustion block in a furnace and its other end adapted to receive gaseous fuel under pressure, and embodying a longitudinal fuel passage therethrough and a duct leading from the atmosphere surrounding the member to the passage, of an igniting device for the burner member comprising means for producing a flame the burner member comprising means for producing a flame and directing such flame toward the duct for passage to the passage in the member, and a rotatable collar on the duct equipped portion of the member having an openingtherein and adapted to be rotated into a position wherein its opening is in registry with the inlet end of the duct during use of the igniting device and after use of the ignitin device and starting of the burner member to be rotated into a position wherein the opening therein is out of registry with said inlet end of the duct.

4. The combination of a tube-like burner member having one end thereof adapted for connec- 7 vsage to the fuel passage in the member, and

means mounted on the duct equipped portion of the member and adjacent to said nozzle for closing the duct against the flow of air therethrough after starting of the burner member.

' DONALD A. CAMPBELL. 

